Marine type muffler



Aug. 27, 1963 T. N. KELLY MARINE TYPE MUFFLER Original Filed Oct. 19, 1960 FIG FIG.3

INVENTOR. THOMAS N. KELLY ATT RN EYS United States Patent 6 3,101,811 MA TYPE MUFFLER Thomas N. Kelly, Detroit, Mich, assig nor to Aircraft Precision Products, Inc, Oak Park, Mich, a corporation of Michigan a I Original application Oct. 19, 1960, Ser- No. 63,633 now Patent No. 3,080,939, dated Mar. 12, 1963. Divided and this application Dec. 11, 1961, Ser. No. 158,265 4 Claims. (Cl. 18l52) The present invention relates to noise suppressors and refers more specifically to a marine type muffier constructed to receive hot exhaust gases and fluid simultaneously and to cool the exhaust gaess, suppress exhaust sound, and discharge the cooled gases and fluid without creating an undesirable and objectionable back pressure.

The present application is a division of my copendmg application, Serial No. 63,638, filed October 19, 1960, and entitled Marine Type Muffler.

An object of the invention is to provide an improved muffler which mixes hot exhaust gases and cooling fluid and is constructed to provide particular flexibility in the mounting thereof and to maintain minimum back pressures.

Another object is to provide an improved rnufller as set forth above which includes a plurality of acoustic filter sections for accomplishing noise suppression and is constructed to utilize hydraulic ram principles to discharge the cooled gases and fluid from an opening adjacent the top thereof.

More specifically, it is an object to provide an improved muffler construction comprising a tubular housing provided at opposite ends thereof with closures and including an inlet tube extending through the closure at one end of the housing and being disposed adjacent and extending lengthwise of one side wall of said housing, and an exhaust tube extending through the closure at the other end of said housing and being disposed adjacent and extending lengthwise of said one side wall of said housing in alignment with said inlet tube.

Another object is to provide a muffler construction as set forth above wherein the housingis divided into .a plurality of resonant chambers of different size for noise suppression by transverse partitions having ducts extending ,therethrough and being disposed against and extending lengthwise of a side wall of said housing in an arrangement which is diametrically opposed to the inlet and exhaust tubes.

Another object is to provide a muffler construction as set forth above wherein the inner end of the inlet tube and the exhaust tube are tapered axially inwardly of the respective tubes and radially inwardly of the housing to provide uniform expansion and exhaust respectively of the gas in the mufller.

Another object is to provide a muffler construction as set forth above wherein the ducts have diameters approaching or exceeding their length so that the ducts will not resonate as open pipes but will function as acoustic coupling ducts.

Another object is to provide a mufller as set forth above which is simple in construction, economical to manufacture and eflicient in use.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawing, illustrating a preferred embodiment of the invention, wherein:

FIGURE 1 is an elevational View of a mufller, partly in section, constructed according to the invention.

FIGURE 2 is an end view looking in the direction of arrows 2-2 of FIGURE 1.

Edd l ,8li Patented Aug. 27, 1963 FIGURE 3 is a sectional view taken on line 3-3 of FIGURE 1.

With particular reference to the drawings a specific embodiment of the present invention will now be disclosed.

As best shown in FIG. 1, the muffler 10 0f the present invention comprises a tubular housing 12, provided with closures 14 and 16 at opposite ends and which is divided into resonant chambers 18, 26* and 22 by partitions 24 and 26 located between the closures l4 and 16 at longitudinally spaced points :of the housing 12. The partitions 24 and 26 have coupling ducts 28 and 30 respectively extending therethrough. An inlet tube 32 extends through closure .14 and is disposed against and extends lengthwise of one side wall of the housing 12. Exhaust tube 34 extends through closure 16 and is disposed against and extends lengthwise of said one side wall of the housing such that the tubes 32 and 34 are aligned and longitudinally spaced from one another.

The mother 1d constructed as shown is particularly adapted to receive a mixture of water and hot exhaust gases from an internal combustion engine through inlet tube 32. The muffler It) is operable to further mix the water and gases to cool the exhaust gases. Mufiier 10 is also constructed to suppress the exhaust noise and discharge the gases and water through the exhaust tube 34 without creating objectionable b ack pressures. In addition, since the exhaust tube 34 i located in the upper portion of the muffier as installed and water is exhausted therefrom by means of hydraulic ram principles rather than -by gravity as previously greater flexibility of mounting of the muffler It) is provided.

More specifically, the housing 12 comprises an elongated cylinder which may be constructed of relatively light weight corrosion resistant material such as titaniumstabilized stainless steel. Closures 14 and 16 which are similar in construction are secured over the opposite ends of the housing 12 by means of the annular flanges 36 and 38 respectively by convenient means such as welding to provide a seal between the closures .14 and 16 and the housing 12.

As indicated best in FIGURE 1 the closure 14 has an opening 443 therethrough adjacent the periphery thereof through which the inlet tube 32 extends. The inlet tube 32 may be secured to the flange 42 around the opening 40 by convenient means for sealing the inlet tube 32 to the closure 14 such as welding. The inlet tube 32 is positioned adjacent the periphery of the closure 14 so that the exhaust gases and water may be introduced into an upper portion of the muffler 10' as installed.

The closure 16 is. also provided with an opening 44 therethrough adjacent the periphery thereof. Flange 46 is provided around the opening 44 to which the exhaust tube 34 may be sealed by convenient means such as welding. The exhaust tube 34 as shown in FIGURE 1 also.

extends through an upper portion of the closure 16 with respect to the muffler 10 as installed and is aligned with and longitudinally spaced from the inlet tube 32.

As will be readily recognized the placing of the exhaust tube 34 in the upper portion of the closure 16 hinders gravity drainage of the cooling water therefrom. It has however been found with mufliers constructed as shown in the drawing that adequate drainage is provided in operation. It is believed that drainage is accomplished due to the pulsation of the gases trom the internal combustion engine (not shown) attached to the muffler. The pulsating gases apparentlyyact on the water in chamber 22 in the manner of the driving force of the well known hydraulic ram to force the water from the exhaust tube e.) gravity water discharge'with the exhaust tube located in the bottom portion of the closure.

Furthermore since the exhaust tube 34 is not required to be located at the bottom of the closure 16 in accordance with the invention as was previously the case to provide adequate drainage for the muffler the exact positioning of the muffler during installation is not required. Thus the end 47 of the mufiler need not be lower than the end 49 thereof. A drain, not shown, is generally provided in the lower portion of the housing :12. Also the mufller 10 may be rotated axially slightly if required in installation. In other words the flexibility in positioning of the muffler 10 constructed as shown in FIGURE 1 is greatly improved over other marine type mufflers.

The inner end 48 of the inlet tube 32 is tapered axially inwardly of the tube 32 radially inwardly of the housing 12 as shown. The tapered end of the inlet tube 32 provides uniform expansion of exhaust gas and water discharged into the chamber 18 therefrom to cause the gas and water to circulate within chamber 18 to most advantageously cool the gases and prevent generation of internal noises within the muffler.

The exhaust tube 34 is similarly provided with an inner end 50 which is tapered axially inwardly of the tube 34 radially inwardly of the housing 12. The tapered end 50 of the exhaust tube 34 permits smooth how of the cooled exhaust gas and water from chamber 22.

Partitions 24 and 26 are circular as shown best in FIGURE 3 and include annular flanges 52 and 54 around the outer periphery thereof which are secured to the housing 12 as shown in FIGURE 1 by convenient means such as welding to provide resonant chambers 18, 20 and 22 as previously indicated. It will be noted that the partitions 24 and 26 are spaced longitudinally of housing 12 so that the chambers 18, 20 and 22 have dilferent dimensions and therefore resonate at different frequencies to produce sound attenuation at the most objectionable .firequencies.

Partitions 24 and 26 are further provided with openings 56 and 58 in the lower portion thereof with respect to the installed rnufiler and diametrically opposed to tubes 32 and 34 as shown in the figures. Flanges 60 and 62 are provided about openings 56 and '58 in partitions 24 and 26 respectively to which the acoustic coupling ducts 28 and 30 are secured by convenient means.

Ducts 28 and 30 have diameters approaching or greater than their lengths as will be evident from inspection of FIGURE 1 whereby the ducts 28 and 30 will not resonate as open pipes but will function as acoustic coupling ducts to couple the sound from chamber 18 into chamber 20 and from chamber 20 into chamber 22.

The ducts 28 and 30 also serve to provide a path through the mufller 10 from the inlet tube 32 to the chamber 22 for the exhaust gases and water discharged into the muffler 10 which is substantially unimpeded so that a low back pressure is created by muffier l and water in chamber 22 is discharged from exhaust tube 34 in the manner in which water is discharged from a hydraulic ram by means of the pulsating exhaust gases.

In operating it will be understood that the mufiler 1.0 is connected with the inlet tube 312 and the exhaust tube 34positioned in the top portion as shown. The mufiler 110 may either be installed level or inclined slightly toward either end 47 or 49 in accordance with the positioning of the drain, not shown.

A combined mixture of hot exhaust gases and water is discharged into chamber 18 through inlet tube 3-2. The hot gases and water are caused to expand uniformly on exit from the inlet tube 32 due to the tapered inner end thereof and are caused to intermingle in chamber 18 as indicated by the flow arrows 64 therein whereby the gas is caused to cool and the sound at the frequency to which the chamber I8 is tuned is suppressed.

' rows 68 and the remaining undesirable noise frequencies are suppressed. The cooled exhaust gas and water then flow smoothly out of the exhaust tube 34 due to the pul- I sating exhaust gases as previously indicated.

The mufller structure 10 of the invention is particularly efficient in silencing the exhaust of internal combustion engines while producing a relatively low back pressure due to the alignment of coupling ducts 28 and 30 and the positioning of the inlet tube 32 and the exhaust tube 34 in the upper portion of the mutfier 1b as shown 111 FIGURE 1 in conjunction with the tapered ends of the tubes 32 and 34.

The arrangement of the inlet and exhaust tubes in the manner specified provides flexibility of installation of the mufller at the expense of little additional back pressure and slightly diminished drainage capabilities than when the tubes are diametrically opposed to one another.

What I claim as my invention is:

1. A marine type muffler comprising an elongated tubular housing, separate inner and outer end headers respectively closing the opposite ends of said housing, a pair of transversely extending partitions secured within said housing in longitudinally spaced relation to said end headers and to each other dividing said housing into first and second resonant chambers respectively adjacent said inner and outer end header-sand a third resonant chamber between said first and second chambers, an inlet tube extending through said inner end header into said first chamber, said inlet tube being disposed adjacent to the side wallof said tubular housing in laterally offset parallel relation to the longitudinal center line of said housing, an acoustical coupling duct extending through and secured to one of said partitions, a second acoustical con- The cooled gases and water together with the unsuppling duct in spaced axial alignment with said first mentioned duct and extending through and secured to the other of said partitions, said chambers in communication with one another and being disposed in laterally offset parallel relation to the longitudinal center line of said tubular housing at the diametrically opposite side of said center line from said inlet tube, the end of said inlet tube within said first chamber lying in a plane inclined radially and axially inwardly relative to said housing at an acute angle to the longitudinal center line of said housing to provide for a uniform flow and expansion of exhaust gases and water into said first chamber, and an outlet tube extending through said outer end header into said second chamber, said outlet tube being in spaced axial alignment with said inlet tube, the end of said outlet tube within said second chamber lying in a plane inclined radially inwardly and axially outwardly relative to said housing at an acute angle to the longitudinal center line of said housing to provide for a smooth flow of exhaust gases and water from said second chamber, the arrangement of said tubes and ducts serving to reduce back pressure in the muffler, the ends of said ducts and the inclined ends of said tubes being open and unobstructed to further reduce back pressure.

2. The muffler defined in claim 1, wherein said third chamber is larger in volume than said second chamber and smaller in volume than said first chamber.

3. The muifler defined in claim 1, wherein each coupling duct is of a diameter closely approaching or exceedingthe length thereof to prevent the same from resonating.

4. The mufller defined in claim 1, wherein said aligned ducts are vertically beneath the longitudinal center line said ducts placing Y of said housing and said aligned inlet and outlet tubes UNITED STATES PATENTS Kenney Oct. 7, 1913 Maxim Sept. 21, 1937 6 Hector et a1. Mar. 126, 1940 Zinsitz June 18, 1940 Maxim et al. Apr, 15, 1941 Leadbetter Oct. 17, 1944 Bourne Feb. 28, 1950 Bourne Aug. 1, 1950 Dugas Jan. 16, 1962 

1. A MARINE TYPE MUFFLER COMPRISING AN ELONGATED TUBULAR HOUSING, SEPARATE INNER AND OUTER END HEADERS RESEPCTIVELY CLOSING THE OPPOSITE ENDS OF SAID HOUSING, A PAIR OF TRANSVERSELY EXTENDING PARTITIONS SECURED WITHIN SAID HOUSING IN LONGITUDINALLY SPACED RELATION TO SAID END HEADERS AND TO EACH OTHER DIVIDING SAID HOUSING INTO FIRST AND SECOND RESONANT CHAMBERS RESPECTIVELY ADJACENT SAID INNER AND OUTER END HEADERS AND A THIRD RESONANT CHAMBER BETWEEN SAID FIRST AND SECOND CHAMBERS, AN INLET TUBE EXTENDING THROUGH SAID INNER END HEADER INTO SAID FIRST CHAMBER, SAID INLET TUBE BEING DISPOSED ADJACENT TO THE SIDE WALL OF SAID TUBULAR HOUSING IN LATERALLY OFFSET PARALLEL RELATION TO THE LONGITUDINAL CENTER LINE OF SAID HOUSING, AN ACOUSTICAL COUPLING DUCT EXTENDING THROUGH AND SECURED TO ONE OF SAID PARTITIONS, A SECOND ACOUSTICAL COUPLING DUCT IN SPACED AXIAL ALIGNMENT WITH SAID FIRST MENTIONED DUCT AND EXTENDING THROUGH AND SECURED TO THE OTHER OF SAID PARTITIONS, SAID DUCTS PLACING SAID CHAMBERS IN COMMUNICATION WITH ONE ANOTHER AND BEING DISPOSED IN LATERALLY OFFSET PARALLEL RELATION TO THE LONGITUDINAL CENTER LINE OF SAID TUBULAR HOUSING AT THE DI- 